Swab



Dec. 5, 1933. A. l.. HAIR 1,938,383

SWAB

Filed May 3, 1930 2 Sheets-Sheet l @www A. L. HAIR Dec. 5, 1933.

SWAB

Filed May 3, 1930 2 Sheets-Sheet 2 Patented Dec. 5, 1933 UNITED STATES PATENT OFFICE 1 Claim.

rlhis invention relates to a device for use in wells and relates more particularly to a swab for bailing out or cleaning well tubing, well casing, etc.

Devices commonly known as swabs are employed to remove or bail mud, sand, cuttings, etc. from the tubing and casing of wells. Swabs are employed principally to swab out or clear the oil tubing of a well so that the oil pump may operate effectively and to permit the free flow of oil through the tubing. The forms of swabs in general use embody rubber packing to slidably engage the walls of the tubing, to clean the tubing and to prevent fluid from passing the swab as it is operated upwardly in the well. The rubber parts or packing wear very rapidly and require frequent replacement.

It is a general object of this invention to provide a swab for use in a well in which the tubing engaging parts or packing may be easily and quickly replaced.

It is another object of the invention to provide a swab that embodies one or more individual packing units or assemblies that may be quickly and easily mounted on and dismounted from the body of the swab.

Another object of the invention is to provide a swab of the character mentioned that passes iiuid as it is lowered into the well and which utilizes the weight or head -of the fluid above it to expand the packing into tight sealing engagement with the tubing so that it positively moves or bails the iluid from the well when pulled from the well.

A further object of the invention is to provide a swab of the character mentioned in which yone or more like replaceable packing carrying units are detachably mounted on a stem or body of uniform size or diameter.

It is a further object of the invention to provide a swab of the character mentioned that is of particularly simple and sturdy construction and is dependable and effective in operation.

Other objects and features of my invention will be best and more fully understood from the followingdetailed description of a typical form and application of the invention, throughout which description reference is had to the accompanying drawings, in which:

Fig. 1 is a longitudinal sectional view of a portion of a well illustrating the swab provided by this invention in operating position in a tubing within the well. Fig. 2 is an enlarged side elevation of the swab. Fig. 3 is a longitudinal detailed sectional view taken as indicated by line (Cl. 10S-225) 3 3 on Fig. 2. Fig. 4 is an enlarged transverse detailed sectional view taken as indicated by line 4 4 on Fig. 2. Fig. 5 is an enlarged transverse detailed sectional view taken as indicated by line 5 5 on Fig. 3. Fig. 6 is an enlarged transverse sectional View taken as indicated by line 6 6 on Fig. 3. Fig. 7 is an enlarged transverse detailed sectional view taken as indicated by line '7 7 on Fig. 2. Fig. 8 is an enlarged longitudinal detailed sectional view taken as indicated by line 8 8 on Fig. 3.' Fig. 9 is an enlarged longitudinal detailed sectional view of the central portion of the device, and Fig. 10 is an enlarged side elevation of the upper portion of the swab.

The device provided by this invention is intended primarily to be operated in wells to swab out or clear the tubing or well casing of sand, fluid, cuttings. etc. The swab may be suitably designed to be operated in casing or tubing of oil wells, water wells, gas wells, etc. and for use with various types of equipment. Throughout the following detailed disclosure I will describe a simple form `o1 the invention particularly adapted to operate in the oil tubing of an oil well. In Fig. 1 of the drawings I have illustrated a portion of a well in which a casing C has been set and have shown the swab provided by this invention in operating position in a tubing 'I extending through the casing. Itis to be understood that the invention is not to be considered as limited'to the particular formvor application about to be described but that it is to be taken as including any features o1' modiiications that may fall within the scope or the claim.

The swab provided by this invention includes, generally, a central body or stem 10 having a. longitudinal iiuid passage l1, means 12 for controlling the passage of iiuid through the opening 11, and one or more replaceable packing assemblies or units A removably mounted on the stem 10 and carrying packing 13 for slidably engaging and sealing with the tubing T.

The stem or body 10 is an elongated member provided to carry the replaceable packing units A. The stem l0 may be a simple unitary member having a main portion 14 and an enlargement 15 at one end of the portion 14. In accordance with the invention the main portion 14 of the body is elongated and is of uniform cross sectional configuration and size throughout its length. In the preferred form of the invention the main portion 14 is of round cross sectional coniiguration. The enlargement 15 is provided at the upper end of the main portion 14 and may be provided with flattened sides 16 so that it may be readily engaged by a suitable tool. The fluid passage 11 extends longitudinally through the main portion 14 of the stem from its lower end to a point within the enlargement 15. Branch ports or openings 17 are provided at the upper end of the opening 11 to discharge at the exterior of the enlargement 15. The branch openings 17 may extend upwardly and outwardly from the upper end of the opening 11 to the exterior of the enlargement 15. The stern 10 may be provided with suitable means to facilitate attachment to an operating cable, or the like. In the particular case shown an upwardly projecting screwthreaded pin 18 is provided on the upper end of the enlargement 15. The pin 18 maybe threaded into a suitable coupling or connecting member. In the particular case illustrated I have shown a length of rod or cable tool stem 20 connected with the stem 10 by a coupling 21 threaded onto the pin 18. The rod 20 may be used in connection with the swab to act as a weight to ensure its proper operation through the tubing T.

The means 12 for controlling the passage of iluid through the opening 11 is provided at the lower end of the opening so that iiuid stands in the opening 11 when the swab is pulled or operated upwardly in the stern 10. The means 12 may be any suitable form of check valve to permit the passage of fluid upwardly through the opening 11 and to prevent the passage of fluid downwardly through the opening 11. In the particular embodiment of the invention illustrated in the drawings, a typical ball check valve is mounted on the lower end of the stem 10. The check valve may include a body or cage 22, a seat member 23 having an upwardly facing seat 24, and a ball 25 to cooperate with the seat 24 to prevent passage of fluid downwardly through the opening 11. The cage or body 22 of the valve may be removably screw-threaded directly onto the lower endr of the stem 10 and its interior communicates with the opening 11. The cage 22 is of larger diameter than the stem 10 so that it presents an upwardly-facing shoulder 26 adjacent the lower end of the stem 10. The seat member 23 may be in the form of a tubular plug screw-threaded into the lower end of the cage 22. A pin 27 may extend transversely through the interior of the cage 22 to prevent the ball 25 from closing the lower end of the opening 11 when the swab is being lowered through the tubing T and uid is passing upwardly through the stem. The cage 22 is screw-threaded onto the lower end of the stem 11 so that it may be readily removed when the packing units A are replaced.

The packing units or assemblies A are removably mounted on the main portion 14 of the stem 10 between the enlargement 15 and the Valve cage 22. There may be any desired number of units A provided on the stem. In the particular casefillustrated there are two substantially like units A arranged longitudinally on the main portion 14.

Each packing assembly or unit A includes, generally, a body 30, expansible packing 13 on the body 30, and collars 32 and 33 for retaining the packing 13 on the body. The bodies 30 of the packing units A are elongated tubular members having central longitudinal openings 34 slidably passing the main portion 14 of the stem 10. The bodies 30 are preferably of round cross sectional configuration and of uniform diameter throughout their lengths. The packing units A may be arranged on the stem 10 so that the upper end of the body 30 of the uppermost unit engages the enlargement l5 and so that the lowerinost unit is positioned between the lower end of the uppermost unit A and the valve cage 22. With this arrangement the upper end of the body 30 of the lower unit may directly engage the body of the upper unit and its lower end may engage the valve cage 22. A portion 14 being of uniform configuration and size throughout its length, the openings 34 of the two bodies 30 are of the same size and shape so that the two units A may be readily slid onto the stern l0 when the valve cage 22 is removed.

In accordance with the preferred form of the invention means is provided for holding the units A against rotation on the Stem 10. In accordance with the broader principles of the invention various forms of releasable joints or connections may be provided between the units A and the stem 10 to prevent rotation of the units on the stern 10. In the particular case illustrated the body 3G of the uppermost section A is engaged by parts on the enlargement 15 of the stem which hold it against rotation on the stem while the bodies 30 or" the two units A are provided with 'cooperating parts holding them against relative rotation. In the form of the invention shown in the drawings the enlargement l5 is provided with downwardly extending projections or lugs 35 to seat in recesses or notches 36 in the upper end of the body 30 of the uppermost unit A. The lugs 35 may have downwardly convergent sides and the notches 36 may be of corresponding shape so that the body 30 may be readily positioned where the lugs 35 extend into the notches 36.

The cooperating parts of the two bodies 30 of the units A provided to prevent relative rota- Q,

tion between the units A may be designed in any manner to releasably connect the bodies 30 against relative rotation. In the particular case illustrated downwardly projecting parts or lugs 37 are provided at the lower end of the body 30 of the upper unit A to seat into notches 38 in the upper end of the body 30 of the lowermost unit A. The sides of the lugs 37 may be downwardly convergent and the notches 33 may be of corresponding configuration so that the units A may be readily arranged in position on the stem 10 where the lugs seat in the notches. The bodies 30 of the units A are proportioned so that the valve cage 22 may be threaded onto the lower end of the portion 14 at the lower end of the body 30 of the lowermost section A to clamp the units on the stem in position where the lugs 35 and 37 will be in retaining position. A suitable lock nut may be arranged between the cage 22 and body 30 of the lower unit A. It will be obvious that the means for retaining the units A on the stern 10 against rotation may be varied considerably without departing from the spirit of the invention. For example, the upper end of the body 30 of the lowermost section A may have lugs or parts to extend into notches or sockets in the lower end of the body 30 of the upper unit A.

l The packing 13 is provided on the bodies 30 of the units A to seal with the interior of the tubing T when the swab is operated upwardly or withdrawn from the well to prevent the passage of uid between the swab and the tubing. There may be a unitary body of packing 13 arranged on the body 30 of each unit A. The packing 13 may be formed of rubber or suitable rubber composiico ict

'lic

tion so that it may be expanded by the weight of the fluid above the swab when the swab is operated upwardly as will be hereinafter described. The packing 13 is detachably or removably mounted on the body 30 of each unit A between the retaining collars 32 and 33. The packing 13 may be annular or tubular having a central longitudinal opening 40 slidably passing the body 3. The opposite end portions of the packing 13 are tapered to seat into sockets in the retaining rings or collars 32 and 33 as will be hereinafter described. The exteriors of the bodies of packing 13 are shaped to effectively seal with the interior of the tubing T. The packing 13 as initially formed is proportioned to freely slide through the tubing T and is such that when it is expanded it effectively seals with the interior of the tubing.

The retaining rings or collars 32 and 33 of each unit A are provided to retain the packing 13 on the body 30 and may be employed to compress the packing. The collar 32 of the upper unit A is carried on the upper end of the body 30, while the collar 32 of the lower unit A is carried at the lower end of the body of the lower unit. The collars 32 are preferably rigidly secured to the bodies 30, for example, they may be welded to the bodies. Each collar 32 is provided with an axially and outwardly projecting annular flange 41 to provide a tapered socket 42 to receive a tapered end of the packing 13. The collars 32 may be provided with attened sides to be engaged by a wrench or tool. In the particular form of the invention shown in the drawings, the collar 32 of the uppermost section A is formed with notches 43 registering with the notches 36 to receive the outer portions of the lugs 35.

The collar 33 of the upper unit A is arranged on the lower end of the body 30 and the collar 33 of the lower section is arranged on the upper end of the body 30 of the lower unit and are provided with axially and outwardly projecting annular flanges 44 which provide tapered sockets 46 for extending over the tapered ends of the packing 13. The collars 33 are preferably slidably arranged on the bodies 30. In the particular arrangement illustrated in the drawings the collar 33 of the upper section A may be operated to compress the packing 13 to cause its expansion, and a locking nut 47 may be threaded on the body 30 to engage the lower end of the collar 33 to set the collar in position. Further, in the arrangement shown the collar 33 of the lower unit A may be operated on the body 30 of that unit to tightly clamp onto or compress the packing 13 by ay locking nut 48 threaded on the body 30 to engage the collar 32.

The invention provides for the utilization of the weight of head of the uid above the swab when the swab is withdrawn from the well .to expand the packing 13 so that it effectively seals the interior of the tubing T. The control means 12 operates to prevent the passage of fluid downwardly through the opening 11 when the swab is operated upwardly in the well. Registering transverse openings 50 are provided in the main portion 14 of the stem and the bodies 30 of the units A to communicate with the opening 11 and annular recesses 51 formed in the walls of the openings 40 of the packing 13. The openings 50 are provided to transmit or pass the iiuid pressure from the opening l1 into the recesses 51 where it acts outwardly on the packing 13 to force it into effective sealing engagement with the interior of the tubing T. The lugs 35 and 37 are related to the openings 50 so that the bodies 30 are in positions on the main portion 14 of the stem so that the openings 50 are always in register.

It is believed that the operation of the swab provided by this invention will be readily apparent from the foregoing detailed description. When the device is lowered into the well on a cable, or the like, fluid in the well is permitted to pass upwardly through the opening 11. When the swab is pulled upwardly to remove or bail the fluid from the well, the ball 25 cooperates with the seat 24 to prevent downward passage of fluid through the opening 11 so that the weight or head of uid above the swab as the swab is pulled upwardly acts to expand the packing 13 into effective sealing engagement with the interior of the tubing T. It is to be noted that the invention provides a swab wherein like packing carrying units are removably arranged on a stem of uniform shape and size. The packing 13 and other parts of the units A, being alike, are interchangeable. The units A may be quickly replaced on the stem by removing the valve cage 22. Further, the packing 13 may be easily removed from the bodies 30 of the units A by removing the retaining collars 33.

Having described only a typical preferred form of my invention, I do not wish to limit myself to the specific details set forth, but wish to reserve to myself any changes or variations that may appear to those skilled in the art or fall within the scope of the following claim.

Having described my invention, I claim:

A swab for use in tubing including, a stern having an integral main portion and a projection at one end of said portion, there being a longitudinal opening in said portion, two like separable packing units removably mounted on the said portion, each unit including a body having an opening slidably passing the said portion, there being lateral openings in the said portion communicating with the opening in the stem and openings in the bodies of the units, expansible packing on each of the bodies having grooves in its inner walks registering with the openings in the bodies, means for holding the units against rotation on the said portion including, a part on the projection removably seated in a notch in one of the bodies, and cooperating parts on adjoining ends of the two bodies holding the bodies against relative rotation, and a check valve removably mounted at the other end of the said portion to prevent the flow of fiuid through the stem in one direction and engaging one of the bodies to removably retain the units on the stem.

ALDON L. HAIR. 

